1. Field of the Invention
The present invention relates generally to a robot and, more particularly, to an improvement in distribution equipment for supplying power, signals, materials or others to a manipulator.
2. Description of the Related Art
In a robot or, especially, an industrial robot, distribution equipment is provided for distributing or communicating various substances (such as electric current, air, inactive gas, water or paint) relating to power, energy, signals, information or materials, for the purpose of the driving control of electric motors in respective control axes in a manipulator, the driving control of an end-effector, the use in the end-effector, the transfer of information to or from various sensors, and so on. In this type of distribution equipment, an umbilical member, such as a cable or a conduit, incorporating signal lines or material feeding lines therein is generally used, and a laying structure is provided, in a robot mechanism including a manipulator, for suitably laying the umbilical member.
In the above-described distribution equipment for the robot, it is required that the umbilical member is not entangled with the manipulator or stretched during the operation of the manipulator. To this end, the conventional laying structure, provided in the robot mechanism, includes a clamp member for clamping the umbilical member at a suitable intermediate position, while providing the umbilical member with a desired slack. In this regard, as the umbilical member is generally laid out between a plurality of members movable relative to each other and across a joint in the manipulator, it is necessary to properly select a position at which the umbilical member is clamped.
For example, in the case where the clamp member is fixedly provided in the robot mechanism, the clamp member is arranged at a position permitting the sufficient slack of the umbilical member, so that the umbilical member is not fully stretcher during a period when the plural members in the robot mechanism are moving relatively. In this case, the reduction in outside dimension of the robot mechanism may be disturbed for the purpose of allowing the larger slack of the umbilical member. Contrary to this, in the case where the clamp member is movably arranged in the robot mechanism, the clamp member can suitably move in correspondence to the relative movement of the plural members in the robot mechanism, whereby it is possible to minimize the slack of the umbilical member between clamped positions and thus to exclude an influence on the outside dimension of the robot mechanism. In this arrangement, however, as the movable clamp member moves under the application of a stretching force to the umbilical member, which results from the relative movement of the plural members in the robot mechanism, the umbilical member may be damaged by the stretching force.